Damascene processing, a semiconductor processing technique, may be used to form interconnections on an integrated circuit. Damascene processing involves the formation of inlaid metal lines in trenches and vias formed in a dielectric layer. In a typical damascene process, a pattern of trenches and vias is etched in the dielectric layer of a semiconductor wafer substrate. A barrier layer, such as tantalum (Ta), tantalum nitride (TaN), or a TaN/Ta bi-layer, is then deposited onto the wafer surface by, for example, a physical vapor deposition (PVD) process. The trenches and vias are then typically filled with copper using an electroplating process. Because electroplating typically needs to occur on a conductive layer, a copper seed layer may be first deposited on the barrier layer with chemical vapor deposition (CVD) or PVD processes. Then, copper may be electroplated onto the copper seed layer.